Electrical switch



A ril 10, 1934. a. s. MOORE ELECTRICAL SWITCH Filed May 9, 1933 JR? 2 72 0y Patented Apr. 10, 1934 UNITED STATES PATENT OFFICE.v

four per cent to Fred H. M

Rowe, Gloucester,

Application May 9, 1933, Serial No. 670,095v

2 Claims.

My present invention relates to electric switches and more particularly to an automatic switch centrifugally operated by rotating bodies.

5 I have provided means for utilizing the centrifugal force exerted by all rotating bodies to open and close a path for an electric circuit asso-' ciated with the said rotating body by displacing a conductor element in a somewhat variable manner. For this displaceable body or member,

I have shown as my preferred embodiment a ball-like mass of mercury for the several reasons that mercury is a conductor of electricity, it has a high specific gravity, it adapts itself to conforming to the shape of container in which it may be held and is particularly susceptible to the action of a centrifugal force exerted upon it. However the same centrifugal principle may be applied to certain conducting solids and liquids which are to be included within the scope of this invention.

The principal object of my invention is therefore an improved electric switch.

Another object is a centrifugal electric switch.

Another object is a centrifugally operated switch adapted to be automatically governed by the speed of rotation of an automobile speedometer cable or other driving mechanism.

Still another object is a centrifugally operated electric switch utilizing a displaceable mercury body.

Still another object is a mercury switch of the above described characteristics associated with the speedometer cable of an automobile adapted I to control certain circuits in an automobile lighting system.

Other objects and novel features comprising the construction and operation of my invention will appear as the description of the same progresses.

' In the drawing illustrating the preferred embodiment of my invention Fig. 1 is a symmetrical cross section of my device mounted about a coupling which is adapted to be actuated by a driving mechanism indicated in broken lines and representing the two ends of a speedometer cable for an automobile.

Referring more in detail to the drawing indicates a housing member preferably iormedof a fibrous material which is threaded at either end into cap members 11 and 12 shown in broken lines. Axially journaled through the boss portions 13 and 14 of caps 11 and 12 respectively are drive members 15 and 16 also shown in broken lines and provided with the shouldered portions 17 and 18. shouldered Portion 17 is iournaled in the cap 13 and the upper end of the housing 10 and is provided with an inner dog extremity 19. shouldered portion 18 is journaled in the cap 12 and the lower end of housing 10 and providcd with a recess 20.

Axially disposed through the housing 10 is a coupling member 21 which is provided with a shouldered extremity 22 journaled in the housing 10 and having a recess adapted to receive the dog extremity 19. Coupling 21 is further provided with a shouldered portion 23 journaled in the housing 10 and having a dog extremity 24 adapted to engage with the recess 20. The drive members 15 and 16 may comprise solid shafts directly driven by steam, gas or electric motors or they may be illustrative of a more flexible system such as the speedometer for an automobile and it is in connection with this latter purpose that my device is to be specifically used.

Solidly secured to the coupling 21 is an upper insulating sleeve member 25 which is preferably composed of a fibrous material and likewise slightly below the upper sleeve member 25 a second lower sleeve member 26 has been secured to the coupling 21.

Surrounding the central portion of the coupling 21 is an iron cup member 2'7 having an upper insulated neck portion 28 solidly secured about the sleeve 25 and a lower insulated neck portion 29 solidly secured about the sleeve 26. Located in the base of the iron cup member 2'? is a mass of mercury 30 which has been shown as spherically shaped but which may be flattened out so as to partly surround the coupling 21, and in either case is adapted to 'act as a conducting element between the cup member 27 and the uninsulated portion of the coupling 21. The upper neck portion 28 is journaled in a metallic bushing member 31 which is solidly mounted in the housing 10. Located through said housing 10 and said bushing 31 at a point directly opposite the neck member 28 is a binding post member 32. The binding post 32 may be connected into any electric circuit where an automatic speedcontrolled switch may be of utility such as the lighting system for a car, the other contact of such a circuit being made through a common ground to which the coupling member 21 is connected. The drawing shows the apparatus in a closed circuit condition with provision for a current to pass through the binding post 32 to bushing 31 to cup member 27 to the mass of mercury 30 to coupling 21 and grounding at the cable.

In operation the coupling 21 is rotated by drive member 16 at a variable rate or speed and the cup member 2'? being solidly secured to the coupling 21 is likewise rotated thereby creating a centrifugal force which tends to lift the mass of mercury 30 away from the coupling 21. As the intensity of the centrifugal force depends upon the speed of rotation of the cup 2'7 which is directly dependant upon the drive members 15 and 16, it may readily be seen that for a given weight of mercury there will be a speedvof rotation of the cup member 2'7 which will force the mercury mass 30 away from the coupling 21 with the resultant opening of the above described electric circuit. This effect will only be maintained while such a speed of rotation is provided and the circuit will become closed again at any time when the speed of rotation drops below a predetermined rat'e audit is further pointed out that both the opening and closing of the circuit are purely automatic with no factor other than the rate of speed of rotation being concerned.

I have shown a preferred embodiment of my invention in which it is to be further understood that various modifications may be resorted to while still continuing to the original spirit of my invention.

Having thus described my invention what i claim is:

1. A centrifugally operated electric switch mechanism comprising a fibrous housing member, shaft members journaled in either end of said housing, a coupling member solidly secured to a cup member solidly fixed said shaft members,

an insulated manner, said to said coupling in shaft members adapted to rotate said coupling and said cup member, a mercury ball located in said cup member adjacent said coupling member and adapted to comprise an electrical connection between said coupling and said cup, said clip member adapted to centrifuge said mercury mass out of contact with said coupling, a binding post member located in said housing member and electrically associated with said cup member adapted to connect said switch mechanism with an electrical circuit.

2. A centrifugally operated electric switch mechanism comprising a fibrous housing member, shaft members journaled at either end of said housing, a coupling member solidly secured to said shaft members, a cup member solidly fixed to said coupling in an insulated manner and having a ball of mercury located in its base and contacting with a portion of the coupling periphery and adapted to comprise an electrical connection between said cupand said coupling, said cup adapted to be rotated and centrifuge said mercury ball out of contact with said coupling, a binding post member located in said housing member and electrically connected to said cup member adapted to connect said switch mechanism with an electrical circuit.

GUY S. MOORE. 

